Cochlear implant (“CI”) systems are known in the art. Such systems allow the profoundly deaf (i.e., those whose middle and/or outer ear is dysfunctional, but whose auditory nerve remains intact) to hear. The sensation of hearing is achieved by directly exciting the auditory nerve with controlled impulses of electrical current, which impulses are generated as a function of perceived audio sounds. The audio sounds are picked up by a microphone carried externally (not implanted) by the deaf person and converted to electrical signals. The electrical signals, in turn, are processed and conditioned by a signal processor to generate a control signal, typically a sequence of pulses of varying width and/or amplitude. The control signal, once generated, is transmitted to an implanted pulse generator of the cochlear implant system. The implanted pulse generator, in response to receipt of the control signal, generates appropriate pulses of electrical current that are applied to one or more electrodes of an electrode array that is inserted into the cochlea of the deaf person. It is this electrical current that directly stimulates the auditory nerve and provides the deaf person (“user”) with the sensation of hearing. Representative cochlear implant systems are described, e.g., in U.S. Pat. Nos. 4,408,608; 4,532,930; 4,947,844; 5,603,726; 6,289,247; 6,754,537; and 7,076,308, incorporated herein by reference.
Most CI systems have a built-in microphone located in the case or housing of the “headpiece” used with the CI system. The headpiece typically includes, in addition to the built-in microphone, an external coil and a magnet. The magnet is used to align the external coil of the headpiece directly over the location where an implanted coil associated with the implanted pulse generator is located. When the external coil and implanted coils are aligned, the external circuits can optimally and efficiently transmit both data and power signals to the implanted circuits of the implanted pulse generator. Disadvantageously, such positioning of the headpiece rarely, if ever, optimally positions the built-in microphone for picking up sound waves.
Because the built-in microphone located in the headpiece does not always sense sound waves in an optimum manner, a popular type of external microphone used with one type of cochlear implant system is a “T-Mic”. A T-Mic is a microphone placed within the concha of the ear near the entrance to the ear canal. Such location is ideal for a microphone because that is the location where sound is naturally collected by the concha of the ear. A T-Mic is described, e.g., in U.S. Pat. Nos. 6,775,389 and 7,020,298, incorporated herein by reference.
The T-Mic is held in its desired position (within the concha of the ear near the entrance of the ear canal) by a boom or stalk that is attached to the ear hook of a behind-the-ear (“BTE”) speech processor. A BTE processor not only includes the signal processing circuitry necessary to receive, amplify and process the signals generated by the microphone in response to sensing audio sounds, but also the circuitry needed to transmit the appropriate control signals to the implanted pulse generator. Additionally, the BTE processor typically carries the batteries needed to power the entire CI system.
In order to keep the BTE processor as light weight and small as possible, it is common to limit the number of accessories that may be attached to it. For example, an exemplary BTE processor employs only a single auxiliary input port. This allows only one accessory to be attached to it at any given time. Thus, while multiple accessories are provided that can be attached to the one auxiliary port of the BTE processor, such as a telecoil, a T-Mic, an FM receiver, and an auxiliary connector (where the auxiliary connector allows an MP3 player, or similar external audio signal source, to be connected directly to the processing circuits of the BTE processor), only one such accessory can be used at any given time.
Many cochlear implant users like to use the T-Mic accessory all the time. When they do so the singular auxiliary input port of the BTE is occupied, thereby preventing users from listening to music or using the hands-free connection feature provided by many cell phones at the same time that the T-Mic is attached to the BTE. Simple splitting of the existing auxiliary port (also referred to herein as the “aux” port) interferes with the T-Mic operation and does not allow simultaneous direct connection of an external audio input and the T-Mic. Therefore, there remains a need for users of the T-Mic to also be able to use an auxiliary port at the same that the T-Mic is being used.
One user of a T-Mic, who does not want to disconnect his T-Mic, but who also wants to be able to have auxiliary sound signals be received as input signals into his BTE processor so that he can hear them, has discovered a way to couple such sounds directly into his T-Mic. Such user acoustically couples a conventional ear bud, attached to his MP3 player, iPod or other auxiliary sound source, directly to his T-Mic. This is done by connecting a first end of a short sound tube over the end of the ear bud and then connecting the other end of the short sound tube over his T-Mic. In this way, sounds broadcast from the ear bud are carried by the short sound tube directly to the T-Mic, where they are electrically sensed and processed by the BTE processor of his CI system.
It is thus seen that there is a need in the art for a CI system having a BTE that allows both a T-Mic and an auxiliary audio input to be connected to the BTE at the same time.